1. Field of the Invention
The present invention relates to a probe card used in measuring electric characteristics of a measurement objective.
2. Description of the Related Art
As a probe card of this kind, there has been available one including a base plate and probes each having a curved portion and attached to the base plate (see Patent literature 1). The probe card is used in a way such that the distal end of a probe is overdriven on an electrode as a measurement objective in contact therewith to bend the curved portion of the probe, whereby not only is a predetermined contact pressure necessary for measurement against the electrode as a measurement objective obtained, but also the distal end is slid on a surface of the electrode as a measurement objective to scrape an oxide film attached on the surface for ensuring stable contact with the electrode as a measuring objective.
Patent literature 1: JP-A No. 2003-215163.
The probes have been disposed at a narrower pitch progressively toward higher complexity in an integrated circuit, leading to a possibility that a curved portion of a probe is brought into contact with the next probe. Hence, it has been difficult to dispose the probes at the narrow pitch.
If rectilinear probes are employed, it is naturally easier to dispose the probes at a narrower pitch, whereas a rectilinear probe cannot divert away an overdriven load, in terms of construction, which could be successfully realized by the probe with a curved portion. Therefore, a rectilinear probe is easily broken and has difficulty obtaining a contact pressure necessary for measurement. Moreover, because it is difficult to scrape an oxide film on an electrode as a measurement objective by sliding the probe sideways on a surface of the electrode, the probe again has difficulty ensuring a stable contact with the electrode as a measurement objective.
If probes are disposed at a narrow pitch, great congestion arises of electrodes and wiring patterns on a base plate connected electrically to the probes, making placement thereof difficult. In this regard as well, it is difficult to dispose the probes at a narrow pitch.